AFM-based determination of interface and interphase interactions

在当前的资助期间，我们与Regine v.Klitze小组合作，使用原子力显微镜(AFM)来表征聚电解质多层膜(PEM)的厚度和膨胀行为。此外，我们建立了由单个分子共价连接在原子力显微镜针尖上的分子探针，并首次获得了垂直于表面(即相间)的质子交换膜的附着能分布数据。在第二个资助期，我们将使用我们的基于原子力显微镜的分子探针来完成质子交换膜中的附着能和水含量的分布。主要的焦点将是用我们的基于原子力显微镜的方法来确定整个多层膜的横向和垂直迁移率。这些测量将得到我实验室的单分子荧光测量和Regine v.Klitzing小组的散射实验的补充。特别令人感兴趣的是分子量依赖、电荷依赖、固体载体的影响和离子的特定效应。然后，这些研究将应用于SPP中研究的其他(不带电荷的)聚合物中间相，即聚苯乙烯和聚丁二烯聚合物。最后，由于系统规模较小，结果可以直接与Christian Holm在同一系统上进行的MD模拟进行比较。

During the current funding period we used atomic force microscopy (AFM) to characterize the thickness and swelling behaviour of polyelectrolyte multilayers (PEMs) in collaboration with the group of Regine v. Klitzing. In addition, we established molecular probes consisting of a single molecule covalently attached to an AFM-tip and got first data on the adhesion energy profile of PEMs perpendicular to the surface (i.e. in the interphase). In the second funding period we will use our AFM-based molecular probes to complete adhesion energy and water content profiles in PEMs. The main focus will be on determining the lateral and perpendicular mobility throughout the multilayer with our AFM-based method. These measurements will be complemented by single molecule fluorescence measurements in my lab and scattering experiments in the group of Regine v. Klitzing. Of particular interest are the molecular weight dependence, charge dependence, the influence of the solid support and ions specific effects. These investigations will then be applied to other (uncharged) polymer interphases investigated in the SPP, namely polystyrene and polybutadiene based polymers. Finally, because of the small system size, the results can directly be compared to MD-simulations performed on the same system by Christian Holm.